Background and Aim: Angiogenesis is essential in the progression and metastasis of solid tumors. It has been proved that increase in angiogenesis within primary solid tumors is actually associated with nodal metastasis and risk prognosis of some malignancies. In contrast, regarding hematologic neoplasms very limited studies have been done. The goal of the present study was to determine MVD (Microvessel density) in acute leukemia and compare it with MVD in normal tissues.

  Materials and Methods: In this study 30 cases with acute leukemia and 30 normal controls were selected. These had been diagnosed and archived in the pathology department of Mashhad Ghaem hospital .Their blocks and slides were prepared and examined. After their final approving, the paraffin blocks were thinly sliced and the slices were immunohistochemically stained for VEGF (Vascular Endothelial Growth Factor) Immunohistochemical slides were evaluated for hot spots of MVD in the tissue in the microscopic field of vision with 400 times magnification.

  Results: MVD or angiogenesis in acute leukemia was 20.2% which was obviously more than that in the controls (6.9%).The difference between the two groups was statistically significant (P<0.001).

  Conclusion: Angiogenesis in acute leukemia is significantly higher compared with the controls (who had normal tissues).But there was no significant difference between acute myeloid leukemia and acute lymphoblastic leukemia.